OK-150 was a shipboard nuclear steam-generating plant (APPU) with a three-reactor modular layout, developed in the 1950s by the design bureau of Gorky Plant No. 92 (now the Afrikantov OKBM in Nizhny Novgorod) under the direction of I. I. Afrikantov. It became the first Soviet marine nuclear power plant: it was the one that equipped the world's first nuclear-powered icebreaker Lenin when it entered service in 1959.
Design and features
The plant comprised three pressurized water reactors fueled with uranium dioxide enriched to 5% uranium-235; the fuel was manufactured at the Machine-Building Plant in Elektrostal. Because no land-based prototype had been built before the icebreaker was constructed, the designers applied a redundancy principle: each of the three reactors had two circulation loops with two main pumps and one standby pump, which could be shut off independently of one another. The elements of the primary circuit were connected by a branching pipe system, the so-called "loop" layout, which was later replaced by the modular layout, then the monoblock layout, and finally the integral layout in reactors of subsequent generations.
Operation and replacement
The icebreaker Lenin's first Arctic navigation with the OK-150 plant began on August 19, 1960, and lasted just over three months: during that time the ship covered more than 10,000 miles, about 7,000 of them in heavy ice conditions, escorting 92 vessels through the Kara Sea and the Laptev Sea. During operation the plant repeatedly required repairs; after another incident involving a radiation leak, the decision was made to get rid of it. On September 19, 1967, in Tsivolki Bay off Novaya Zemlya, a cut was made in the icebreaker's hull in the area of the reactor compartment, and the entire compartment was lowered through the bottom into the sea by means of an explosive charge.[1] In the vacated space a more advanced two-reactor plant, the OK-900, was installed, which served on the Lenin until the ship was withdrawn from service in 1989.[1]
Place in the history of marine reactors
The OK-150 began the line of Soviet and Russian marine nuclear power plants. It was followed by the OK-900, then by reactors of the KLT-40 and KLT-40S series, which became the basis of the Arktika- and Taymyr-class icebreakers and of the floating nuclear power plant Akademik Lomonosov. The culmination of this evolution was the integral RITM-200 plant, developed by the same Afrikantov OKBM: in it the steam generators are placed inside the reactor vessel for the first time, which made it possible to halve the mass and dimensions compared with its predecessors while increasing power output.
Sources
- helion-ltd.ru — Removal of the OK-150 nuclear plant from the icebreaker Lenin